Support custom timestamp property (#67)

* Add support for custom timestamp key

* Add missing documentation entry

Readme.md

@@ -62,6 +62,8 @@ pino app.js | pino-pretty
   error like objects. Default: `err,error`.
 - `--messageKey` (`-m`): Define the key that contains the main log message.
   Default: `msg`.
+- `--timestampKey` (`-m`): Define the key that contains the log timestamp.
+  Default: `time`.  
 - `--translateTime` (`-t`): Translate the epoch time value into a human readable
   date and time string. This flag also can set the format string to apply when
   translating the date to human readable format. For a list of available pattern
@@ -124,6 +126,7 @@ with keys corresponding to the options described in [CLI Arguments](#cliargs):
   errorProps: '', // --errorProps
   levelFirst: false, // --levelFirst
   messageKey: 'msg', // --messageKey
+  timestampKey: 'time', // --timestampKey
   translateTime: false, // --translateTime
   search: 'foo == `bar`', // --search
   ignore: 'pid,hostname' // --ignore

bin.js

@@ -15,13 +15,15 @@ args
   .option(['l', 'levelFirst'], 'Display the log level as the first output field')
   .option(['k', 'errorLikeObjectKeys'], 'Define which keys contain error objects (`-k err,error`)', 'err,error')
   .option(['m', 'messageKey'], 'Highlight the message under the specified key', CONSTANTS.MESSAGE_KEY)
+  .option(['a', 'timestampKey'], 'Display the timestamp from the specified key', CONSTANTS.TIMESTAMP_KEY)
   .option(['t', 'translateTime'], 'Display epoch timestamps as UTC ISO format or according to an optional format string (default ISO 8601)')
   .option(['s', 'search'], 'Specify a search pattern according to jmespath')
   .option(['i', 'ignore'], 'Ignore one or several keys: (`-i time,hostname`)')
 
 args
   .example('cat log | pino-pretty', 'To prettify logs, simply pipe a log file through')
   .example('cat log | pino-pretty -m fooMessage', 'To highlight a string at a key other than \'msg\', use')
+  .example('cat log | pino-pretty -a fooTimestamp', 'To display timestamp from a key other than \'time\', use')
   .example('cat log | pino-pretty -t', 'To convert Epoch timestamps to ISO timestamps use the -t option')
   .example('cat log | pino-pretty -t "SYS:yyyy-mm-dd HH:MM:ss"', 'To convert Epoch timestamps to local timezone format use the -t option with "SYS:" prefixed format string')
   .example('cat log | pino-pretty -l', 'To flip level and time/date in standard output use the -l option')

index.js

@@ -3,7 +3,7 @@
 const chalk = require('chalk')
 const jmespath = require('jmespath')
 const colors = require('./lib/colors')
-const { ERROR_LIKE_KEYS, MESSAGE_KEY } = require('./lib/constants')
+const { ERROR_LIKE_KEYS, MESSAGE_KEY, TIMESTAMP_KEY } = require('./lib/constants')
 const {
   isObject,
   prettifyErrorLog,
@@ -30,6 +30,7 @@ const defaultOptions = {
   errorProps: '',
   levelFirst: false,
   messageKey: MESSAGE_KEY,
+  timestampKey: TIMESTAMP_KEY,
   translateTime: false,
   useMetadata: false,
   outputStream: process.stdout
@@ -40,6 +41,7 @@ module.exports = function prettyFactory (options) {
   const EOL = opts.crlf ? '\r\n' : '\n'
   const IDENT = '    '
   const messageKey = opts.messageKey
+  const timestampKey = opts.timestampKey
   const errorLikeObjectKeys = opts.errorLikeObjectKeys
   const errorProps = opts.errorProps.split(',')
   const ignoreKeys = opts.ignore ? new Set(opts.ignore.split(',')) : undefined
@@ -83,7 +85,7 @@ module.exports = function prettyFactory (options) {
     const prettifiedLevel = prettifyLevel({ log, colorizer })
     const prettifiedMessage = prettifyMessage({ log, messageKey, colorizer })
     const prettifiedMetadata = prettifyMetadata({ log })
-    const prettifiedTime = prettifyTime({ log, translateFormat: opts.translateTime })
+    const prettifiedTime = prettifyTime({ log, translateFormat: opts.translateTime, timestampKey })
 
     let line = ''
     if (opts.levelFirst && prettifiedLevel) {

lib/constants.js

@@ -7,6 +7,8 @@ module.exports = {
 
   MESSAGE_KEY: 'msg',
 
+  TIMESTAMP_KEY: 'time',
+
   LEVELS: {
     default: 'USERLVL',
     60: 'FATAL',

lib/utils.js

@@ -7,6 +7,7 @@ const {
   DATE_FORMAT,
   ERROR_LIKE_KEYS,
   MESSAGE_KEY,
+  TIMESTAMP_KEY,
   LOGGER_KEYS
 } = require('./constants')
 
@@ -309,11 +310,12 @@ function prettifyObject ({
 }
 
 /**
- * Prettifies a timestamp if the given `log` has either `time` or `timestamp`
- * properties.
+ * Prettifies a timestamp if the given `log` has either `time`, `timestamp` or custom specified timestamp
+ * property.
  *
  * @param {object} input
  * @param {object} input.log The log object with the timestamp to be prettified.
+ * @param {string} [input.timestampKey='time'] The log property that should be used to resolve timestamp value
  * @param {bool|string} [input.translateFormat=undefined] When `true` the
  * timestamp will be prettified into a string at UTC using the default
  * `DATE_FORMAT`. If a string, then `translateFormat` will be used as the format
@@ -323,10 +325,10 @@ function prettifyObject ({
  * `undefined` is returned. Otherwise, the prettified time is returned as a
  * string.
  */
-function prettifyTime ({ log, translateFormat = undefined }) {
-  if ('time' in log === false && 'timestamp' in log === false) return undefined
+function prettifyTime ({ log, timestampKey = TIMESTAMP_KEY, translateFormat = undefined }) {
+  if (timestampKey in log === false && 'timestamp' in log === false) return undefined
   if (translateFormat) {
-    return '[' + formatTime(log.time || log.timestamp, translateFormat) + ']'
+    return '[' + formatTime(log[timestampKey] || log.timestamp, translateFormat) + ']'
   }
-  return `[${log.time || log.timestamp}]`
+  return `[${log[timestampKey] || log.timestamp}]`
 }

test/lib/utils.public.test.js

@@ -191,6 +191,15 @@ tap.test('prettifyTime', t => {
     t.is(str, undefined)
   })
 
+  t.test('returns prettified formatted time from custom field', async t => {
+    let log = { customtime: 1554642900000 }
+    let str = prettifyTime({ log, translateFormat: true, timestampKey: 'customtime' })
+    t.is(str, '[2019-04-07 13:15:00.000 +0000]')
+
+    str = prettifyTime({ log, translateFormat: false, timestampKey: 'customtime' })
+    t.is(str, '[1554642900000]')
+  })
+
   t.test('returns prettified formatted time', async t => {
     let log = { time: 1554642900000 }
     let str = prettifyTime({ log, translateFormat: true })